Heat sink



FIG. 1 is an isometric view of a heat sink showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is similar to FIG. 1, but shown in a second state; and,

FIG. 9 shows the heat sink of FIG. 1 being mounted to a retention module and having a fan mounted thereon, wherein the retention module and the fan are shown for illustrative purpose only and form no part of the claimed design. 

The ornamental design for a heat sink, as shown and described. 